Potency test for vaccine formulations

Abstract

The invention relates to certain methods for the determination of an antigen content of a first antigen in a mixture comprising two or more antigens. The invention also relates to a potency test for an antigen in a combination vaccine. The method allows the determination of the antigen content in a mixture additionally comprising antibodies that are capable of binding with the antigen.

The invention claimed is: 
     
       1. A method for the determination of an antigen content of a porcine circovirus type 2 (PCV-2) antigen in a mixture of at least a first composition comprising the PCV-2 antigen and a second composition comprising (i) a  Mycoplasma hyopneumoniae  ( M. hyo ) antigen and (ii) antibodies directed against the PCV-2 antigen that are capable of binding with the PCV-2 antigen, the method comprising the steps of,
 a) mixing together the first and second compositions, 
 b) dissociating antigen-antibody complexes in a sample of the mixture, formed between the PCV-2 antigen and the antibodies, and 
 c) determining the antigen content of the PCV-2 antigen by means of an immunoassay. 
 
     
     
       2. The method of  claim 1 , wherein the immunoassay is an ELISA (enzyme linked immunosorbent assay). 
     
     
       3. The method of  claim 1 , wherein the mixture is a ready-to-use vaccine formulation. 
     
     
       4. The method of  claim 1 , wherein the sample of the mixture is incubated with an acid solution to dissociate the antigen-antibody complexes. 
     
     
       5. The method of  claim 4 , wherein the acid solution is a citric acid solution. 
     
     
       6. The method of  claim 4 , wherein the sample of the mixture is incubated with the acid solution for at least 8 hours. 
     
     
       7. The method of  claim 4 , wherein the sample of the mixture is incubated at a ratio (v/v) between the acid solution and the mixture selected from the group consisting of at least 25, 25-75, and 25-50. 
     
     
       8. The method of  claim 4 , wherein the pH range of the acid solution is pH 1.0-3.0. 
     
     
       9. The method of  claim 1 , wherein the method is a potency test of a combination vaccine. 
     
     
       10. The method of  claim 3 , wherein the sample of the mixture is incubated with an acid solution to dissociate the antigen-antibody complexes. 
     
     
       11. The method of  claim 10 , wherein the acid solution is a citric acid solution. 
     
     
       12. The method of  claim 10 , wherein the sample of the mixture is incubated with the acid solution for at least 8 hours. 
     
     
       13. The method of  claim 10 , wherein the sample of the mixture is incubated at a ratio (v/v) between the acid solution and the mixture selected from the group consisting of at least 25, 25-75, and 25-50. 
     
     
       14. The method of  claim 10 , wherein the pH range of the acid solution is pH 1.0-3.0. 
     
     
       15. The method of  claim 2 , wherein the sample of the mixture is incubated with an acid solution to dissociate the antigen-antibody complexes. 
     
     
       16. The method of  claim 15 , wherein the acid solution is a citric acid solution. 
     
     
       17. The method of  claim 15 , wherein the sample of the mixture is incubated with the acid solution for at least 8 hours. 
     
     
       18. The method of  claim 15 , wherein the sample of the mixture is incubated at a ratio (v/v) between the acid solution and the mixture selected from the group consisting of at least 25, 25-75, and 25-50. 
     
     
       19. The method of  claim 15 , wherein the pH range of the acid solution is pH 1.0-3.0.